☀️ Cyanuric Acid (Stabilizer)
granular CYA / 'conditioner' · updated August 2026
Quick answer: add 13 oz per 10,000 gallons to raise Stabilizer 10 ppm. Ideal Cyanuric Acid (Stabilizer): 30–50 ppm. Add ½–⅔ first, circulate, retest.
Safety — read first
- • Add through the skimmer sock method or pre-dissolve; don't retest for 3–7 days.
- • Over ~70 ppm CYA your chlorine becomes sluggish — dilute rather than add more chlorine forever.
Sunscreen for your chlorine: without 30–50 ppm CYA, UV burns off outdoor-pool chlorine in hours. But it only goes up — dose carefully.
Side effects: Dissolves very slowly (up to a week). There is no chemical to lower CYA — only draining and refilling water. Don't overshoot.
Dosing chart
| Pool size | +10 ppm | +20 ppm | +30 ppm | +50 ppm |
|---|---|---|---|---|
| 5,000 gal | 6.5 oz | 13.0 oz | 1.2 lb | 2.0 lb |
| 10,000 gal | 13.0 oz | 1.6 lb | 2.4 lb | 4.1 lb |
| 15,000 gal | 1.2 lb | 2.4 lb | 3.7 lb | 6.1 lb |
| 20,000 gal | 1.6 lb | 3.3 lb | 4.9 lb | 8.1 lb |
| 30,000 gal | 2.4 lb | 4.9 lb | 7.3 lb | 12.2 lb |
Calculate your exact dose
1 · Your pool's volume
Working with 20,000 gallons
2 · What are you fixing?
Ideal Cyanuric Acid (Stabilizer): 30–50 ppm. Adjusting pH? Doses aren't linear — see soda ash / muriatic acid.
3 · Add one of these
Estimates from standard label dosing, to raise Cyanuric Acid (Stabilizer) by 40 ppm in 20,000 gallons. Add ½–⅔ of the dose first, circulate 4–6 hours, retest, then top up. Never mix chemicals with each other.
FAQ
How much cyanuric acid do I add per 10,000 gallons?+
13 oz per 10,000 gallons will raise Stabilizer 10 ppm. Scale linearly with your pool size — the chart on this page covers 5,000 to 30,000 gallons.
What does cyanuric acid do to a pool?+
Sunscreen for your chlorine: without 30–50 ppm CYA, UV burns off outdoor-pool chlorine in hours. But it only goes up — dose carefully. Side effect to know: Dissolves very slowly (up to a week). There is no chemical to lower CYA — only draining and refilling water. Don't overshoot.
Is cyanuric acid safe to handle?+
Add through the skimmer sock method or pre-dissolve; don't retest for 3–7 days. Over ~70 ppm CYA your chlorine becomes sluggish — dilute rather than add more chlorine forever.